Rajendra Pachauri, who chairs the UN panel on climate change, today expressed disbelief at the news that the body had jointly won the Nobel peace prize with Al Gore.

"I can't believe it, overwhelmed, stunned," Mr Pachauri told reporters and colleagues after receiving the news on the phone at his office in Delhi, India.

"I feel privileged sharing it with someone as distinguished as [the former US vice-president]."

Earlier this year, the UN intergovernmental panel on climate change (IPCC) made the strongest link yet between human activities and global warming.

The panel, set up in 1988, forecast that all regions of the world would change as a result of warming and that a third of the Earth's species would vanish if global temperatures continued to rise and reached 2C (3.6F) above the average temperature in the 1980s-90s.

"I expect this will bring the subject to the fore," Mr Pachauri said.

The environmental group Friends of the Earth said it also hoped that the win would lead to more action to combat the problem.

"Al Gore and the IPCC have done a huge amount to bring global attention to climate change and have set out positive steps for how we can tackle it," the group said in a statement.

"We hope the signal sent by the Nobel foundation will be heard by politicians around the globe and that urgent action will be taken to address this threat before it's too late."

Greenpeace said it hoped that the award would provide impetus to UN talks in Bali in December to extend the Kyoto protocol, a treaty that set binding limits on greenhouse gases emitted by industrialised countries.

At a US-sponsored conference in Washington last month, the US president, George Bush, said a long-term goal for reducing global warming was needed, but added that each nation should design its own strategy.

Mr Bush also emphasised the need for a voluntary approach to emissions rather than binding targets.

Chris Miller, the global warming campaign director of Greenpeace USA, said: "By awarding this prestigious prize to the former vice-president of the US, the Nobel committee joins the growing chorus of people calling on the US to participate in the international effort to solve the climate crisis."